Engineering Commons^™

An Analysis Of Resistance Spot Weld Quality Based On Acoustic And Electrical Signatures, Ivan Charles Butler

Theses and Dissertations--Manufacturing Systems Engineering

The union of a set of materials by way of Resistance Spot Welding is designed so that once fused together, a substantial amount of intentional, external force must be applied to separate the contents. Therefore, Resistance Spot Welding is often the preferred fusion method in high-volume manufacturing processes. The result of Resistance Spot Welding however is the formation of a weld nugget which is not visible to the naked eye. Destructive and/or ultrasonic methods applied off-line must be used to determine the quality of each weld; both inefficient and expensive processes. The following research analyzes the data fed back during …

Combined Trajectory, Propulsion, And Battery Mass Optimization For Solar-Regenerative High-Altitude Long Endurance Unmanned Aircraft, Nathaniel S. Gates, Kevin R. Moore, Andrew Ning, John D. Hedengren

Faculty Publications

Combined optimization of propulsion system design, flight trajectory planning and battery mass optimization for solar-regenerative high-altitude long endurance (SRHALE) aircraft through a sequential iterative approach yields an increase of 20.2% in the end-of-day energy available on the winter solstice at 35 deg N latitude, resulting in an increase in flight time of 2.36 hours. The optimized flight path is obtained by using nonlinear model predictive control to solve flight and energy system dynamics over a 24 hour period with a 15 second time resolution. The optimization objective is to maximize the total energy in the system while flying a station-keeping …

Sae Baja Custom Caliper And Upright Design, Katelynn R. Kise

Williams Honors College, Honors Research Projects

The Zips Baja Off-Road Racing team had a successful 2018 season however some aspects of the car needed to be updated and improved for the 2019 season. This reports captures the design cycle performed to improve the cost, integration, and reliability of the front braking caliper and upright.

Leveraging Contracting Strategies With Private Shipyards For Increasing Naval Fleet Operational Availability, Kaitlynn M. Castelle, Joseph M. Bradley, Sanjeev Gupta

Engineering Management & Systems Engineering Faculty Publications

A major rethink of NAVSEA’s shipyard contracting strategy is required to support the critical need of improving our naval fleet availability. Operational Fleet material availability is reduced when various parts of the “NAVSEA production system” operate at cross-purposes. By increasing alignment between major players (i.e., NAVSEA and the private shipyards), major improvements in delivery performance, cost, and even throughput can be realized. Developing strategies and specific actions to do so is a rich field given the current state of the system. We take an analytical as well as evidence-based approach to propose strategies that can be successful given the peculiar …

Roadnet: Robust Adaptive Network For Information Diffusion In Vanet, Priyashraba Misra

Graduate Theses, Dissertations, and Problem Reports

The automotive industry has changed more in the last one decade than ever before. Rapid advancements in autonomous driving have opened up opportunities for CAVs (Connected and Automated Vehicles). Vehicles today rely on a sensor-suite to map the surrounding and use that information for safety and navigation. The sensor's view is limited to its line of sight and this drawback can be tapered off by using Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I), generally referred to as Vehicle to Everything (V2X) communication. In this thesis, we specifically focus on utilizing V2V communication using on-board Dedicated Short Range Communication …

การตรวจสอบรอยแตกร้าวบนพื้นผิวคอนกรีตในรูปแบบมัลติสเกลโดยการประมวลผลภาพ, ปิยวัฒน์ ตันติ์ศรีสกุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

รอยร้าวบนพื้นผิวคอนกรีตอาจจะมีลักษณะความแตกต่างตามสาเหตุที่เกิดขึ้น หากได้มีการตรวจสอบในระดับที่ใกล้ชิดกับพื้นผิวรอยร้าว แล้วสามารถนำมาวิเคราะห์แยกลักษณะความแตกต่างของรอยร้าวตามสาเหตุที่เกิดขึ้นได้ ก็จะได้รูปแบบที่จะช่วยลดขั้นตอนการตรวจสอบและเพิ่มขีดความสามารถของบุคลากรในการตรวจสอบรอยร้าวได้ งานวิจัยนี้เป็นกรณีศึกษา โดยตั้งสมมติฐานลักษณะความแตกต่างของรอยร้าวตามสาเหตุที่ได้กำหนด จากนั้นทำการหล่อและทดสอบตัวอย่างคอนกรีตที่ได้กำหนดไว้ คือ การทดสอบแรงดัด การทดสอบแรงเฉือนและการทดสอบแรงดึง จากนั้นนำ Chula Smart Lens ที่มีกำลังขยาย 20, 40 และ 50 เท่า มาใช้งานร่วมกับโทรศัพท์มือถือ Iphone7 ในการถ่ายรูปรอยร้าวที่เกิดขึ้นบนพื้นผิวคอนกรีตและนำภาพถ่ายไปวิเคราะห์โดยการสร้างแบบจำลองและกระบวนการประมวลผลภาพ เพื่อหาลักษณะความแตกต่างและตรวจวัดรอยร้าวที่เกิดขึ้นที่พื้นผิวบนคอนกรีต ผลจากงานวิจัยลักษณะรอยร้าวบนพื้นผิวคอนกรีตจากการสร้างแบบจำลองและการประมวลผลภาพ พบว่ามีบางส่วนเป็นไปตามสมมติฐาน แต่มีบางส่วนที่ไม่เป็นไปตามสมมติฐาน ดังนั้น สมมติฐานลักษณะความแตกต่างของรอยร้าวที่ได้ตั้งไว้ตามสาเหตุที่ได้กำหนดจึงไม่เป็นจริง ส่วนการตรวจวัดรอยร้าวคอนกรีตนั้นสามารถหาค่าความกว้าง ความยาวและพื้นที่ของรอยร้าวที่เกิดขึ้นได้การการประมวลผลภาพ เมื่อรู้ค่าดังกล่าวแล้วสามารถที่จะนำไปหาวิธีในการซ่อมแซมบำรุงรักษาต่อไป

Effect Of Sensor Errors On Autonomous Steering Control And Application Of Sensor Fusion For Robust Navigation, Shuvodeep Bhattacharjya

Dissertations, Master's Theses and Master's Reports

Autonomous steering control is one the most important features in autonomous vehicle navigation. The nature and tuning of the controller decides how well the vehicle follows a defined trajectory. A poorly tuned controller can cause the vehicle to oversteer or understeer at turns leading to deviation from a defined path. However, controller performance also depends on the state–feedback system. If the states used for controller input are noisy or has bias / systematic error, the navigation performance of the vehicle is affected irrespective of the control law and controller tuning. In this report, autonomous steering controller analysis is done for …

Investigation And Development Of Exhaust Flow Rate Estimation Methodologies For Heavy-Duty Vehicles, Chakradhar Reddy Vardhireddy

Graduate Theses, Dissertations, and Problem Reports

Exhaust gas flow rate from a vehicle tailpipe has a great influence on emission mass rate calculations, as the emission fractions of individual gases in the exhaust are calculated by using the measured exhaust flow rate. The development of high-end sensor technologies and emission pollutant measurement instruments, which can give instantaneous values of volume concentration of pollutants flowing out of the engine are gaining importance because of their ease of operation. The volume concentrations measured can then be used with the instantaneous exhaust flow rate values to obtain mass flow rates of pollutants.

With the recent promulgation of real world …

Modeling Chevy Volt Gen Ii Supervisory Controller In Charge Sustaining Operation, Saurabh Bhasme

Dissertations, Master's Theses and Master's Reports

This report is focused on the development of Chevy Volt Gen II powertrain supervisory controller modeling for charge sustaining operation of the vehicle. The modeling process incorporated vehicle parameters and maps provided. The overall powertrain model along with the supervisory controller is developed in MAT- LAB/SIMULINK programming platform. The powertrain model includes all components which are the IC engine, two electric motors & associated TPIM, Battery, transmission auxiliary pump and spin-losses. The supervisory controller includes the vehicle drive mode selection model, the torque blending logic for charge sustaining along with friction brake modeling. The model has been developed to perform …

Mpc-Based Autonomous Driving Control With Localized Path Planning For Obstacle Avoidance And Navigating Signalized Intersections, Sai Rajeev Devaragudi

Dissertations, Master's Theses and Master's Reports

Connected and autonomous vehicles are becoming the major focus of research for the industry and academia in the automotive field. Many companies and research groups have demonstrated the advantages and the requirement of such technology to improve the energy efficiency of vehicles, decrease the number of crash and road accidents, and control emissions.

This research delves into improving the autonomy of self-driving vehicles by implementing localized path planning algorithms to introduce motion control for obstacle avoidance during uncertainties. Lateral path planning is implemented using the A* algorithm combined with piecewise Bezier curve generation which provides an optimum trajectory reference to …

An Experimental Study Of A Passive Nox Adsorber (Pna) For The Reduction Of Cold Start Diesel Emissions, Conor Berndt

Dissertations, Master's Theses and Master's Reports

Medium and heavy-duty diesel engines contribute nearly a third of all NOx emissions nationwide. Further reduction of NOx emissions from medium and heavy-duty diesel engines is needed in order to meet National Ambient Air Quality Standards (NAAQS) for ambient particulate matter and ozone. Current diesel engine aftertreatment systems are very efficient at reducing NOx emissions at exhaust temperatures above 200 °C, however at exhaust temperatures below 200 °C there are significant NOx emissions at the tailpipe. Therefore, a reduction of diesel engine cold start and low speed/load operation emissions, where exhaust temperatures are below 200 °C, is needed. Utilizing a …

Anti-Roll Bar For Sae Baja Vehicle, Jennifer Bulgrin, Zachary A. Gnabah, Scott P. Toth

Williams Honors College, Honors Research Projects

This report explores the need to improve the Zips Baja vehicle handling performance. This will be achieved by designing an anti-roll bar system for the rear suspension of the Zips Baja vehicle to decrease the turning radius of the vehicle. The project develops specific goals to achieve increased performance, goes through the engineering design cycle to create a prototype, evaluate its effectiveness, optimize the design through several iterations, and design a final solution. After sub-functions have been determined, conceptual ideas for completing all sub-functions were evaluated and a conceptual design was selected to proceed into the embodiment design phase. Once …

Carbon Fiber Racing Wheel, Megan Sanok, Melissa Furdak, Sydney Schipani

Williams Honors College, Honors Research Projects

Industry today thrives off of competition; everybody wants their product to be the best. Across almost every field of manufacturing and design, there is a pattern of factors that companies strive for when producing their specialized products. The most effective companies can create a commodity that is relatively inexpensive, easy to manufacture, and has the ability to meet high standards. As engineers, it is ingrained in us that there is always room for improvement, and that we have been given the tools to make it happen.

When evaluating what needed to be improved in our daily lives, the SAE Zips …

Decarbonising The Automotive Industry: The Future For Irish Motorists., Robert Maher

Theses

This research study is an examination of the current state of the Irish automotive industry, which is being reshaped by the imminent shift to electric vehicles. This transition is designed to assist in solving Ireland's air quality and environmental challenges in line with the worldwide move to combat climate change. The research topic of the decarbonisation of the automotive industry determined the research question: "Decarbonising the Automotive Industry: The Future for Irish Motorists". This inquiry focuses on private cars owned for social, pleasure and domestic use. Secondary research was completed to verify the most prevalent and current existing information. A …